1. Field of Invention
The field of the currently claimed embodiments of this invention relates to optical coherence tomography (OCT) systems and methods of use, and more particularly to OCT systems and methods that include tracking of both magnitude and direction of transverse motion.
2. Discussion of Related Art
In optical coherence tomography (OCT), motion tracking is critical for the development of free-hand OCT systems that require correction of motion artifacts to improve image quality and for flow measurements for micro-circulation studies. Optical Doppler tomography (ODT) has been widely used in flow measurement and motion tracking in the axial direction (Z. P. Chen, T. E. Milner, S. Srinivas, X. Wang, A. Malekafzali, M. J. C. van Gemert, and J. S. Nelson, “Noninvasive imaging of in vivo blood flow velocity using optical Doppler tomography,” Opt. Lett. 22(14), 1119-1121 (1997); G. Liu, W. Qi, L. Yu, and Z. Chen, “Real-time bulk-motion-correction free Doppler variance optical coherence tomography for choroidal capillary vasculature imaging,” Opt. Express 19, 3657-3666 (2011)). We have also developed methods for transverse flow measurement and transverse motion tracking based on speckle decorrelation analysis (X. Liu, Y. Huang, and J. U. Kang, “Distortion-free freehand-scanning OCT implemented with real-time scanning speed variance correction,” Opt. Express 20, 16567-16583 (2012); X. Liu, Y. Huang, J. C. Ramella-Roman, S. Mathews, and J. U. Kang, “Quantitative transverse flow measurement using OCT speckle decorrelation analysis,” Opt. Lett. 38, 805-807 (2013)). However, our speckle decorrelation method only extracts the speed, not the direction of the motion. Therefore, there remains a need for improved OCT systems and methods that can provide both magnitude and direction of motion of the OCT system relative to an object under observation.